Control system.



v C. C. .HEINZMAIINf CONTROL SYSTEM.' APPLIQATIOI FILED 00T. 11, 1912.

'1,076,2`O7, Patented o@t.21,1913.

@Haven e LA noms revus Incinncwnsmnnm v CLARENCE C. HEINZMANN, OF INDIANAPOLIS, INDIANA.

CONTROL SYSTEM.

Specication of Letters Patent.

Patented Oct. 21, 1913.

Appnc'amn ma october `11, 1912. seriai No. 725,133.

To all whom t may concern: l l

Be it known that I, CLARENCE C. HEINZ- MANN, citizen of the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have invented a new and useful Control System, of which the following is a specification.

In the operation and automatic control of dampers of heating furnaces, it is customary to provide a mechanical motor by means of which the draft and check dampers may be alternately opened and closed, and such mechanical motor is controlled by a detent, which, in turn, is controlled by the action of an electromagnet controlled by means of a thermostat arranged within the 'l room whose temperature is to be substantially maintained. In the operation of such a device, it has been found that, where a common form of batteryl is used as the source of electrical energy, the battery will, in thecourse of time, become weakened to such an extent as to be unable to operate the control. detent of the mechanical motor,

and if such a condition arises at a time when the draft damper of the furnace is open there is danger of overheating the furnace to such an extent as to set adjacent portions of the building on fire.

Means has heretofore been provided to insure against the maintenance of an open draft diimper at a time when the mechanical motor is run down, and the object of 4my present invention is to provide simple means to insure against the maintenance of an open draft damper as a result of the weakening of the source of electrical ener y controlling the electromagnet of the mec Vanical motor.

Thel accompanying drawings diagrammatically illustrate my invention.

In the drawings, 10 indicates a mechanical motor of any usual or desirable form,

f said' mechanical motor in the arrangement shown, comprising a lever 11, a camv 12 operating upon the lever, a rotary catch member 13 controlling the cam and in this case having two teeth 13', a detent 14' coperating with the teeth of the rotary catch member, and an electromagnet 15 arranged to operate upon the detent 14. As is usual in such a construction, the leverV 11 is connected by a chain 16 with a draft damper 17, and by a chain 18 with a check damper 19 in .such manner that when one of the dampers 1s opened the other is closed.

The magnet 15 has one side of coil connected by a wire 2() with theterminal 21 of the thermostat and the same side ofthe coil by a Wire v22 with the terminal 23 of said thermostat, the intermediate terminal 24e-of the thermostat being connected by a wire 25 with one side of a battery 26, the other side of the battery being connected by a wire 27 with the opposite side of the coil ofthe magnet. The connection of the Wires 2O and 22 to the coil of the magnet 15 is conveniently through a distributer 30 operated by the motor, by which distributer onlyJ one of such Wires is connected tothe coil at a time, and s uch connection is broken and the connection of the other Wire made upon the movement caused by an energization of the magnet 15.

The arrangement 1s such that whenever.,

the intermediate terminal 24 of the thermostat engages terminal 21, the magnet 15 will be energized so as to Withdraw detent 14 and permit the motor to move the dampers in such way as to close the draft damper. If now the battery has weakened to such an extent that it is probably incapable of accomplishing-two m'ore energizations of the electromagnet l5 it is desirable that .the battery be prevented from energizing the electromagnet one more time, and therefore I place a resistance 28 in the wire 22 of sufiicient amount to require considerable more voltage to energize the electromagnet when this connection is made than when the opposite connection is made. This may be. accomplished either by including a separate resistance inthe Wire 22, orby making such Wire itself of smaller cross section or otherwise of higher resista-nce throughout.v

In the production of new apparatus embodying my invention, I am of the opinion that .it is commercially desirable to use a three-wire cable for the connection between the thermostat, motor, and battery, in which cable one of the Wires has materially higher resistance than one of the others, and such two Wires of higher and lower resistance are the wires 22 and 20 respectively.

I' claim as my invention:

1. The combination with a damper-regulating motor comprising yan electromagnet, of a thermostat having high temperature and low temperature terminals, a source of elec trical energy, and electrical connections between said energy source, electromagnet, and thermostat terminals, the circuit including `one of said thermostat terminals having materially higher resistance than the circuit including the other of said terminals.

2. The combination with a damper-regulating motor comprising0 an electromagnct, of a thermostat comprising high temperature and low temperature terminals, a source of electrical energy, electrical connections between said electromagnet, energy-source, and thermostat terminals, and means arranged within the electrical circuit connecting the electromagnet and that thermostat terminal Which will be in-active circuit when the desired minimum temperature is reached,

to prevent energization of said electromagnet when the voltage of the energy-source has decreased below a desired value but is still capable of operatively energizing said electromagnet through the circuit compris ing the opposite thermostat terminal.

3. The combination of an electromagnetically controlled damper-regulating motor, a

source of' electrical energy, and a thermostat having high and low temperature terminals and controlling the Jconnections of said source of electrical energy to the electro- 'magnetic controlling means of said motor,

the circuits respectively controlled by the two thermostat terminals being so related that a higher voltage of the source of electrical energy is required to cause the operation of the motor to produce an increase trolled motor,v a battery, and a'controlling device automatically responsive to predetermined conditions and controlling the cone nections of said battery to the electrically controlled motor through a plurality of alternative circuits .one of which requires a higher voltage ofthe battery to produce operation of the motor than does another.

'5. The combination of 4a motor, an electrically operated controlling device therefor, a source of electrical energy of Variablevoltage, anda controlling device automatically responsive to predetermined conditions and controllingthe connections of said source to the, electrically operated controlling device through a plurality of alternative circuits one of Wl'iich'requires la higher voltage of the source of electrical energy to produce operation of the electrically operated controlling device than does another.

In Witness whereof, I havehereunto set my hand and seal at Indianapolis, Indiana, this seventh day of October, A. D. one thousand nine hundred and twelve.

CLARENCE c.. HriNzMANN. a. 8.]

Witnesses:

G. B. ScHLEY, MAr'LAYDEN.

(lorliexs4 of this patent may beiohtaned for five cents each, by addressing the Commissioner of atntS,

Washington, ID. C. 

